Hello @Khushboo Kumari ,
Welcome to Microsoft Q&A Platform. Thank you for reaching out & hope you are doing well.
I understand that you would like to know how the cost is calculated in case of Azure ExpressRoute.
Please find the below article which describes how you can plan for and manage costs for Azure ExpressRoute.
Refer: https://video2.skills-academy.com/en-us/azure/expressroute/plan-manage-cost
You can use the Azure pricing calculator to help plan for ExpressRoute costs before you add any resources for the service to estimate costs.
https://azure.microsoft.com/en-in/pricing/calculator/
Azure ExpressRoute has three different circuit SKU: Local, Standard, and Premium. The way you're charged for your ExpressRoute usage varies between these three SKU types.
With Local SKU, you're automatically charged with an Unlimited data plan. With Standard and Premium SKU, you can select between a Metered or an Unlimited data plan.
Inbound data transfer is included in the monthly cost of the ExpressRoute circuit for all three SKUs, except when using the Global Reach add-on. Outbound data transfer is only included for an unlimited data plan. For a Metered data plan, outbound data transfer is charged per GB used based on the zone number of your ExpressRoute peering location.
For zone mapping information, please refer the below doc:
https://video2.skills-academy.com/en-in/azure/expressroute/expressroute-locations-providers#partners
Then using an ExpressRoute gateway to link a virtual network to the ExpressRoute circuit, will add on to the cost. ExpressRoute Gateways are charged at an hourly rate plus the cost of an ExpressRoute circuit.
ExpressRoute Global Reach is an add-on you can enable for ExpressRoute and ExpressRoute Direct to link ExpressRoute circuits together. Inbound and outbound data transfer is charged per GB used depending on the zone number of the peering location.
Once you start using Azure ExpressRoute, you can monitor costs using cost analysis in Azure portal.
Kindly let us know if the above helps or you need further assistance on this issue.
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